Recently, with progress of test technologies, blood tests such as a serum biochemistry test, serum immunology test, blood cell test and the like are widely spread, contributing significantly to prevention of diseases and early diagnosis. As blood collecting tubes and preservation containers for blood used in blood tests, specimen containers in tests, and the like, there are often used blood testing containers comprising a blood testing bottomed tube in the form of bottomed tube having open one end and closed another end, and a stopper for a blood testing bottomed tube sealing the opening of the blood testing bottomed tube.
Conventionally, as the blood testing bottomed tube, those made of glass, or plastics such as polyethylene terephthalate, polystyrene, polymethyl methacrylate, polyethylene are often used, and blood testing bottomed tubes made of plastics sometimes exert a significant influence on the test value of a blood test by adhesion of blood clot and blood cells on the inner wall surface in a blood test. Particularly, when blood clot and blood cells adhered cannot be peeled even by centrifugal separation, hemolysis arises, blood blot and blood cells remaining in a blood testing bottomed tube peel before a test and mix into serum and plasma for test, resultantly, a correct test cannot be conducted, in some cases.
Then, in a blood testing bottomed tube intending extraction of serum and plasma, for the purpose of cleanly peeling adhered blood by centrifugal separation, a coating agent is usually applied on the wall surface of a blood testing bottomed tube.
As such coating agents used in a blood testing bottomed tube, there are generally used hydrophobic silicone oils such as polydimethylsiloxane and the like, and hydrophilic modified silicone oils.
However, when a hydrophobic silicone oil is used, there is a problem that blood clot and fibrin easily adhere to a blood testing bottomed tube, or the foam in blood is not de-foamed for a long period of time, by this, a significant influence is exerted on the results of a blood test. A hydrophilic modified silicone oil is eluted in blood or causes a mutual action with blood, and depending on test items, the test results are influenced in some cases, becoming problematic.
Further, also on the stopper for a blood testing bottomed tube for sealing the opening of a blood testing bottomed tube, a coating agent is usually applied in the same manner as for a blood testing bottomed tube. This is applied for the purpose of performing a role as a lubricant in plugging a blood testing bottomed tube with a stopper, in addition to cleanly peeling blood adhered to a stopper by centrifugal separation.
As such a coating agent on a stopper, hydrophobic silicone oils such as polydimethylsiloxane and the like are used. Japanese Kokoku Publication Hei-5-73174 discloses a polyoxyalkylene modified silicone oil as a coating agent for a stopper, and such a hydrophilizated modified silicone oils is also used.
However, there is a problem with the hydrophobic silicone oil that a significant influence is exerted on the result of a blood test by a tendency of adhesion of blood clot and fibrin to a stopper easily and by a fact that foam in blood is not de-foamed for a long period of time. The hydrophilic modified silicone oil has a problem that it is eluted in blood and causes a mutual action with blood, resultantly, depending on test items, an influence is exerted on the test result, in some cases. Further, these silicone oils have a problem that in production, in packing and transportation, and in use, by contact of a blood testing bottomed tube with a stopper, the silicone on the stopper moves to the blood testing bottomed tube, resultantly, the blood testing bottomed tube becomes sticky, and it becomes difficult to paste labels on the blood testing bottomed tube.